Nope, I tried to spot the sending unit from above but couldn't see it. I guess I'll have to get under it.

You can also see it thru the passenger side wheel well, look above the oil filter.
To remove the sender you need to remove the oil filter bracket, easy enough but the top left hand bolt is in a tight spot and will need an open end wrench and patients to remove it.
Do this bolt first and leave one of the bottom bolts last because the bracket is under spring tension (oil pump). If your planning on modding the engine now would be a good time to upgrade the oil pressure spring and piston, the oil pressure kit is available from Intense-racing and worth it imo.
My sensor died this spring and when I swapped out the sensor I also installed the oil pressure kit from Intense, if you have any q'* just ask.

I have the same exact problem - just started yesterday after coming back from a 500 mile trip! Car has a little over 60k miles on it. Will probably take to the dealer next week to replace the sending unit.

Carter

Well this morning I started up the car to heat it up and when I got in it I noticed that my oil pressure was 120psi - no fluctuation at all. I am going to follow the tips for finding it, testing it, and replacing it. I will post back to update. Has anyone else who has experienced this problem resolved it themselves and found that it was just the sending unit? Anyone have any part numbers for this?

I had to replace mine just two days ago for exactly the same symptoms. I didn't do it myself but had it done at the dealership, but I do have the part number off of my invoice:

GM 12584940 Sensor $54.75

cajun

Edited to add that I guess I should point out that this part fits the 2000 SE with the 3.8 L engine. Not sure if there is a difference from year to year.

Mines doing the same thing. I'm going to leave work a little early so I can get home and test mine. None of the parts houses around me have one in stock, so if it'* bad I'll be ordering a GP Sorensen one (Part# OPS192) from Advanced tonight. I'll report on my findings.

I've never used GP Sorensen parts before, but I searched the site and the few times they were mentioned people were saying good things. Anyone know of a reason to stay away from this brand?

$47 from my local pontiac dealer
$54 from the buick dealer

Should be fine...I've used the parts before.

[/quote]

I had to replace mine just two days ago for exactly the same symptoms. I didn't do it myself but had it done at the dealership, but I do have the part number off of my invoice:

GM 12584940 Sensor $54.75

cajun

Edited to add that I guess I should point out that this part fits the 2000 SE with the 3.8 L engine. Not sure if there is a difference from year to year.[/quote]

Same part number installed for me - fixed the problem !

Carter

PDad, When i did mine ,I didnt remove the anything but my Pass. wheel and wheel well...
of course I lost a little bit of oil once the sender was removed.... I just felt like ripping everything out cuz that thing was a PITA!!!